REGENERATED CHITIN FILM FROM THE SOLUTION OF TRICHLOROACETIC-ACID SYSTEMS

Regenerated chitin films were made by casting chitin solutions in mixtures of trichloroacetic acid (TCA) and halogenohydrocarbons such as dichloromethane, chloroform, and 1, 2-dichloroethane (DCE). The acidic binary solvents of DCE and TCA (25∼67wt%) dissolve chitin. The best amount of TCA was 35‼40 wt%. The chitin solution was stored for three days below 15°C or for six hours at 15°C without significant decomposition. Rapid decomposition of the chitin in the solution at room temperature (27‼32°) was suggested from the decrease of the tensile strength of the films prepared from this solutions. The casting films in optimum conditions had tensile strength of 9.4 to 9.5 kg/mmmm2, and were quite tough, hygroscopic and cellophane-like. Elemental analyses of the films indicated the same composition as the purified native chitin, which was supported by infrared spectrum. © 1979, The Society of Polymer Science, Japan. All rights reserved.